Computer wont detect graphics card

[remains]

Ok so I bought a gateway gt5028 a few days ago which originally had windows MCE installed on it, however it was not running very well so I reformatted and put Windows XP pro on it and now only the onboard 6100 video card works, the PNY 6600 which my friend put in a few years is not detected anymore, its not even listed in the device manager. I have: updated the motherboard and video drivers, gone into the system BIOS and enabled the pci-e graphics switch, among other things I tried gateway support but the warranty has expired so they will not help me. Any help would be greatly appreaciated!!

 

[copenhagenlc]

Ok lets narrow this down a little bit.

The 6600 when plugged in will show the POST screen, BIOS, and windows loading correct, but will not display anything within windows right?

 

[remains]

No I can't get anything at all to display when I plug my monitor into the 6600

 

[megamanx00]

Go into the BIOS and disable the onboard video, then try to use your 6600.

 

[remains]

Go into the BIOS and disable the onboard video, then try to use your 6600.

I already did that.

 

[remains]

You tried removing and re-seating the video card and locking it in?

Make sure you turn off computer, turn off power supply switch and hit the power button a few times to expel any remaining power in the mobo capacitors before removing video card or memory.

Yeah I tried re-seating the video card a few times, I will try it again following your instructions though.